Remove the request.isAsyncOperation() method and the associated plumbing as res.getWriteListener() != null does the same thing with less code.
Add a (currently unimplemented) dispatch() line from READ_WRITE_OP to the state diagram.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1477543 13f79535-47bb-0310-9956-ffa450edef68